RT Journal Article SR Electronic T1 Mass eradication of Helicobacter pylori to reduce gastric cancer incidence and mortality: a long-term cohort study on Matsu Islands JF Gut JO Gut FD BMJ Publishing Group Ltd and British Society of Gastroenterology SP 243 OP 250 DO 10.1136/gutjnl-2020-322200 VO 70 IS 2 A1 Tsung-Hsien Chiang A1 Wei-Jung Chang A1 Sam Li-Sheng Chen A1 Amy Ming-Fang Yen A1 Jean Ching-Yuan Fann A1 Sherry Yueh-Hsia Chiu A1 Yi-Ru Chen A1 Shu-Ling Chuang A1 Chun-Fu Shieh A1 Cheng-Ying Liu A1 Han-Mo Chiu A1 Hung Chiang A1 Chia-Tung Shun A1 Ming-Wei Lin A1 Ming-Shiang Wu A1 Jaw-Town Lin A1 Chang-Chuan Chan A1 David Y Graham A1 Hsiu-Hsi Chen A1 Yi-Chia Lee YR 2021 UL http://gut.bmj.com/content/70/2/243.abstract AB Objective Although mass eradication of Helicobacter pylori has been proposed as a means to eliminate gastric cancer, its long-term effects remain unclear.Design Mass eradication of H. pylori infection was launched in 2004 and continued until 2018 for a high-risk Taiwanese population aged 30 years or older dwelling on Matsu Islands with prevalent H. pylori infection. Test positives for the 13C-urea breath test underwent eradication therapy. We evaluated the effectiveness of the mass eradication in reducing two main outcomes, incidence and mortality rates of gastric cancer, until the end of 2016 and 2018, respectively.Results After six rounds of mass screening and eradication, the coverage rate reached 85.5% (6512/7616). The referral rate for treatment was 93.5% (4286/4584). The prevalence rates of H. pylori fell from 64.2% to 15.0% with reinfection rates of less than 1% per person-year. The presence and severity of atrophic gastritis and intestinal metaplasia also decreased with time. Compared with the historical control period from 1995 to 2003, the effectiveness in reducing gastric cancer incidence and mortality during the chemoprevention period was 53% (95% CI 30% to 69%, p<0.001) and 25% (95% CI −14% to 51%, p=0.18), respectively. No significant changes were noted in the incidence rates of other digestive tract cancers or the antibiotic resistance rate of H. pylori.Conclusion Population-based eradication of H. pylori has significantly reduced gastric cancer incidence with no increase in the likelihood of adverse consequences. A significant reduction in mortality is likely to be achieved with a longer follow-up period.Trial registration number NCT00155389